German Pat. OS No. 24 34 604, having a counterpart in U.S. Pat. No. 3,998,131 shows a two section steering spindle connected by a torque rod. One section carries a steering wheel and the second section connects to a rack and pinion for actuating a steering linkage. The two sections coact as a rotary control valve in a well known manner, having relative rotation for valving control.
Intermediate the sections ball bearings are carried in radial bores in one section and rest in V-notches on the other. The outer sides of the ball bearings are exposed to servomotor pressure. The greater the pressure and the greater the relative rotation, the greater the detent effect of the ball bearings in the notches. This simulates steering resistance.
There is a disadvantage in that the slightest imperfection in machining the notches prevents the ball bearings from maintaining simultaneous contact with the notches in neutral steering position, causing a difference in simulated steering resistance for one steering direction as compared with the other. Further, the ball bearings have too short a sealing length against the pressure on their outer sides so that under low operating pressure conditions, sensitivity of reaction to simulate steering resistance suffers accordingly.